The Kingdom of Germany or German Kingdom (Latin: regnum Teutonicorum 'kingdom of the Germans', regnum Teutonicum 'German kingdom', regnum Alamanie "kingdom of Germany", German: Deutsches Königreich) was the mostly Germanic language-speaking East Frankish kingdom, which was formed by the Treaty of Verdun in 843. The king was elected, initially by the rulers of the stem duchies, who generally chose one of their own. After 962, when Otto I was crowned emperor, East Francia formed the bulk of the Holy Roman Empire, which also included the Kingdom of Italy and, after 1032, the Kingdom of Burgundy.
Like medieval England and medieval France, medieval Germany consolidated from a conglomerate of smaller tribes, nations or polities by the High Middle Ages. The term rex teutonicorum ('king of the Germans') first came into use in Italy around the year 1000. It was popularized by the chancery of Pope Gregory VII during the Investiture Controversy (late 11th century), perhaps as a polemical tool against Emperor Henry IV. In the 12th century, in order to stress the imperial and transnational character of their office, the emperors began to employ the title rex Romanorum (king of the Romans) on their election.